He never regained consciousness after he was struck from behind by a hit-and-run driver on his regular Friday morning ride down Petaluma Hill Road from his home near campus to Penngrove, where he met with friends for breakfast.

Norwick, 68, had recently retired from the Environmental Studies and Planning Department, where he taught for nearly four decades.

A Rohnert Park man, Robert Cowart, also 68, was arrested several hours after Norwick was struck and was charged with felony hit-and-run driving.

CHP Officer Jon Sloat said Wednesday authorities would seek to upgrade those charges.

Prosecutors earlier said a vehicular manslaughter charge would be likely if Norwick did not recover.